abstract-reader.hpp

#ifndef OPENEV_READERS_ABSTRACT_READER_HPP
#define OPENEV_READERS_ABSTRACT_READER_HPP
 
#include "openev/containers/queue.hpp"
#include <atomic>
#include <cstddef>
#include <mutex>
#include <thread>
 
namespace ev {

class AbstractReader_ {
public:
  virtual ~AbstractReader_();
  AbstractReader_(const AbstractReader_ &) = delete;
  AbstractReader_(AbstractReader_ &&) noexcept = delete;
  AbstractReader_ &operator=(const AbstractReader_ &) = delete;
  AbstractReader_ &operator=(AbstractReader_ &&) noexcept = delete;

  AbstractReader_(const std::size_t buffer_size, const bool use_threading);

  inline Queue &data() {
    if(!eof_ && buffer_.size() < bufferSize_) {
      if(!updateBuffer_()) {
        eof_.store(true);
      }
    }
    return buffer_;
  }
 
protected:
  const std::size_t bufferSize_;
  std::thread thread_;
  Queue buffer_;
  std::mutex bufferMutex_;
  std::atomic<bool> threadRunning_{};
  std::atomic<bool> eof_{false};
 
  virtual bool updateBuffer_() = 0;
 
private:
  void threadFunction();
};
 
} // namespace ev
 
#endif // OPENEV_READERS_ABSTRACT_READER_HPP